Automatic letter underscoring mechanism



y 1970 L. E. PALMER 3,509,992

AUTOMATIC LETTER UNDERSCORING MECHANISM Filed Feb. 14, 1968 5 Sheets-Sheet 1 FIG. 1

INVENTOR.

LEON E. PALMER ATTORNEY.

May 5, 1970 L. E. PALMER AUTOMATIC LETTER UNDERSCORING MECHANISM 8 Sheets-Sheet 2 Filed Feb. 14 1968 FIG. 2b

May 5, 1970 1.. E. PALMER AUTOMATIC LETTER UNDERSCORING MECHANISM 3 Sheets-Sheet 5 Filed Feb. 14

United States Patent US. Cl. 197-113 4 Claims ABSTRACT OF THE DISCLOSURE The automatic underlining of a character after it is typed is accomplished by the incremental rotation of a cam which moves a pair of cam followers. The first cam follower disconnects the escapement mechanism from the torque bar on alternate movements of the cam. The second cam follower activates the underline character selecting interposer on alternate movements of the cam. The cam is moved by a ratchet wheel and ratchet driver which is adapted to be driven by the cycling of the filter shaft. When the mechanism is placed in its operative mode by the locking-down of a control button, the cycling of the filter shaft during the normal operation initiated by the pressing of a character button moves the ratchet driver which causes the ratchet wheel and cam to rotate an increment and place the cam followers on the high dwell such that the escapement mechanism is disconnected and the underline character selecting interposer is activated. This causes underline character to be struck in the same space as the selected character. The second cycling of the filter shaft caused by the activation of the underline character selecting interposer results in another incremental movement of the ratchet wheel and cam, causing the cam followers to return to the low dwell. This reconnects the escapement mechanism, so that the typewriter escapes following the printing of the underline character, and releases the underline character selecting interposer to place the apparatus in condition to select and print the next character.

Background of the invention In typing, it is often desirable to print a second character in the same space as the first, for example, when it is desired to underline a letter, Word, or series of words. Heretofore, this has required the typist to backspace to the character to be underlined and then strike the underline key. This is a time consuming operation and can easily result in errors due to the underlining of the wrong character.

US. Pat. 1,818,078 and US. Pat. 2,093,581 each show apparatus for automatic underlining. In 1,818,078, the character is printed first and the underline key is structured to strike back under the character after an escapement. This is accomplished by providing an underscoring typebar mounted on the typewriter adjacent the striking point of the regular typebars. In 2,093,581, the underline is struck first and there is no escapement with the underline because it is structured so as to not operate the escapement mechanism. In both cases while the back-spacing operation is eliminated, the underline key must still be operated and the change in the structure and operation of the underline mechanism precludes its use in a normal manner.

Summary of the invention An apparatus has now been provided which permits the automatic typing of a second character in the same space as the first selected character and which is particularly adapted to automatic underlining in typewriting machines having a single printing element. The apparatus permits the underline to be operated in a normal manner if desired.

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In accordance with this invention, there is provided an automatic character underscoring mechanism for a typewriter comprising a means for first simultaneously disconnecting the escapement mechanism and activating the underscore selecting interposer of the typewriter when any character selection button is activated and then reconnecting the escapement mechanism and returning the underscore selecting interposer to the start position automatically whereby the selected character is first printed without escapement, the underline character is then printed under the selected character, followed by escapement and return of the typewriter to a condition for the typing of the next character. A control means is provided to place the automatic character underscoring mechanism in either an operative or an inoperative mode so that the underline can be used in a normal manner if it is so desired.

Description of the drawings FIG. 1 is a diagrammatic representation of a typewriter in which the mechanism of the invention is incorporated.

FIGS. 2a, 2b, and 20 represent various conditions of selected portions of the typewriting apparatus of FIG. 1 during the automatic underscoring mode of operation.

Detailed description The foregoing and other objects, features and advantages of the invention will be apparent from the following more particular description of a preferred embodiment of the invention, as illustrated in the accompanying drawmgs.

Turning now to FIG. 1 there is shown in diagrammatic form a single element typewriter such as that disclosed in Palmer U.S. flat. 2,919,002. The typewriter has a single printing element 11 which has a plurality of characters embossed thereon and which is mounted on a rocker platform 13 that is pivotally mounted on a rocker shaft 15. The printing element 11 is first selectively tilted and r0- tated in order to position a desired character for printing and is then actuated against paper 17 which is positioned around platen 19 when a key lever 21 is depressed to effect printing of the selected character.

A motor 23 continuously drives a shaft 25 by means of a pulley 27 and a belt 29. The shaft 25 is selectively coupled to a cycle shaft 31 through a clutch mechanism 33, which is like that described in US. Pat. 2,919,002 and which includes a helical spring, not shown, which is normally retained in an unwound condition under the control of a clutch sleeve 35, and a clutch latch 37 which engages a step 39 on the sleeve 35.

Associated with keylever 21 is a keybutton 41 and character selecting interposer 43. Depression of keybutton 41 causes keylever 21 to strike portion 42 of interposer 43, moving interposer 43 from its rest position. Movement of the interposer 43 results in a selective rotation and tilting of print element 11 as described in the aforementioned Palmer patent, through the medium of selector bails, not shown.

The interposer 43 has several lugs 43a and 43b extending downwardly therefrom. Certain of the lugs 43a control the head selection function. Another lug 43b operates against a cycle bail 45 to move it downwardly. The bail 45 through a link (not shown) causes a pivoting of latch 37 which releases the clutch sleeve 35. This results in actuation of clutch 33 and rotation of cycle shaft 31. The cycle shaft 31 rotates during each print cycle, and through gears 47, 49 and 51 causes a 180 rotation of filter shaft 51.

The filter shaft 51 has a double bladed portion 53 which is positioned just below the ends of all of the interposers, such as end portion 430 of interposer 43. The bladed portion 53 engages a step (not shown) on interposer 43 when interposer 43 is in a down condition and, during the rotation of filter shaft 51, forces interposer '43 to the left in FIG. 1 to operate the character selection mechanism. Following the typing of the selected character on paper 17, the print element 11 is moved one space in the direction of printing in order that it be positioned opposite a new printing position on paper 17 by an escapement mechanism operating through linkage 55, lever 57 and torque bar 59.

Normally, in order to underscore the character selected and printed by means of pressing keybutton 41, it is necessary to first actuate the backspace mechanism (not shown) of the typewriter to bring the printing element 11 back to a position opposite the printed character and then to strike keybutton 61 to move underscore character selecting interposer 63 downwardly to cause the printing element 11 to print the underscore under the printed character. The invention eliminates the necessity of carrying out the underscoring as a separate operation as follows.

Automatic underscore keybutton 65 has a bar portion 67 which is mounted through a slot 69 in frame71. Bar portion 67 has a cut out portion 73 adapted to engage edge 75 of slot 69 such that keybutton 65 can be locked in the down position. Bar portion 67 has an aperture 77 adapted to receive the end 78 of spring 79. End 80 of spring 79 is mounted on frame 71 such that spring 79 will return keylever 65 to its start position when out out portion 73 is unlatched from edge 75. Pin 81 on bar portion 67 engages surface 83 of aperture 85 of ratchet driver 87 such that when keylever 65 is latched down, end 89 of ratchet driver 87 is moved down such that step 91 of ratchet driver 87 is in the path of bladed portion 53 of filter shaft 51. End 93 of ratchet driver 87 is adapted to contact ratchet teeth 95 of ratchet wheel 97 which is mounted to rotate with shaft 99. Ratchet wheel 97 is held in position against travel in a clockwise direction by wheel 101 of pawl 103 which is pivotally mounted by a pin 105 attached to the typewriter frame (not shown). Wheel 101 is held in contact with ratchet wheel 97 by spring 107 mounted between pawl 103 and a portion of the typewriter frame (not shown). Mounted to rotate with ratchet wheel 97 and shaft 99 is cam 109 having lobes 111. Ratchet wheel 97 has twice as many teeth 95 as cam 109 has lobes 111. Ratchet wheel 97 has as many teeth 95 as cam 109 has lobes 111. Cam follower 113 has a pin 115 adapted to ride on cam 109 and is mounted to permit lateral movement by means of a pin 117 fixed to the typewriter frame (not shown) passing through aperture 119 in cam follower 113. Pin 115 is urged into contact with the surface of cam 109 by means of spring 121 connected to cam follower 113 at 123, the other end of spring 121 is connected to the typewriter frame (not shown). End 125 of cam follower 113 is adapted to contact a portion 127 of lever 57 which lever is disengageably connected to torque bar 59 through bifurcated portion 60.

Cam follower 129 has a pin 131 mounted at end 133 adapted to contact the surface of cam 109. Cam follower 129 is mounted to the typewriter frame by a pin 135 passing through aperture 137 which is of sufficient height to permit the vertical movement of follower 129 caused by the riding ofpin 131 of the cam 109. Cam follower 129 has a horizontal portion 141 adapted to contactthe top side 140 of underscore character selecting interposer 63. Cam follower 129 has an aperture 143 adapted to receive shaft 99, the aperture 143 being of sufficient length to permit thefull vertical movement of cam follower 129 caused by the riding of pin 131 on cam 109.

The operation of the mechanism is illustrated in FIGS. 2a, 2b, and 20. Turning now to FIG. 2a, keybutton 65 is shown in the latched-down position bringing step 91 of rachet driver 87 into the path of bladed portion 53 of filter shaft 51. Depressing keybutton 41 is shown in FIG. 2b moves interposer 43 through means of portion 22 of keylever 21 into the path of bladed por- 4 tion 53 of filter shaft 51 and the several lugs 43a of interposer 43 cause the rotation and tilting of printing element 11 (FIG. 1) to select the correct character through the medium of selector bails (not shown). Lug 43b actuates cycle bail 45 causing the clutch mechanism 33 (FIG. 1) to engage and rotate cycle shaft 31 (FIG. 1) which results in the rotation of filter shaft 51 and the printing of the selected character. The rotation of the filter shaft 51 also causes bladed portion 53 to contact step 91 of ratchet driver 87, moving ratchet driver 87 to the left, causing ratchet wheel 97 to be rotated counterclockwise one tooth as shown in FIG. 2c and held there by wheel 101 of pawl 103. Spring 88 then causes ratchet driver path 87 to move back to the right into the bladed portion 53a of filter shaft 51 which has rotated 180 such that end 93 of ratchet driver 87 moves from contact with ratchet tooth 95a to ratchet tooth 95b as is shown in FIG. 20 and indicated by the dot. The rotation of shaft 99 caused by the rotation of ratchet wheel 97 also rotates cam 109 so that the pins 115 and 131 of cam followers 113 and 129 are moved to the top of lobes 111 of cam 109. Because there are twice as many ratchet teeth as there are lobes in the cam, this first operation causes the cam to stop with the followers 113 and 129, on the high dwell and this position is maintained pending a further filter shaft operation.

When cam follower 113 moves to the right as shown in FIG. 20, it contacts surface 127 of lever 57 causing bifurcated portion 60 of lever 57 to be disconnected from torque bar 59. Since the escapement occurs late in the letter cycle, i.e., not until after the printing operation, the escapement mechanism is disconnected from the torque bar such that no escapement occurs with the printing of the selected character. At'the same time that cam follower 113 has caused the escapement mechanism to be disconnected, the downward movement of cam follower 129 causes the horizontal portion 141 to pull down on the top 140 of underscore character selecting interposer 63 so that step 64 is in the path of filter shaft 51 and lug 63b contacts bail 45. A second printing cycle is thus automatically initiated and a second rotation of the filter shaft occurs through the action of lugs 63a and 63b on cycle bail 45 and character selector bails (not shown). The second rotation of the filter shaft 51 causes ratchet driver 87 to move to the left with a resulting incremental movement of ratchet wheel 97, shaft 99, and cam 109. This returns the mechanism 113 and 129 to the condition shown in FIG. 2a, in that lever 57 is urged by the action of spring 145 to the left and reconnects escapement linkage to torque bar 59.

Therefore, following the printing of the underline character under the first selected character on paper 17 by printing element 11, the movement of the printing element 11 to the next printing position on the paper takes place. At the same time, the return of cam follower 129 to the position shown in FIG. 2a releases character selecting inter-poser 63 so that the typewriting machine is ready for the next print cycle. The movement of the ratchet wheel during the sequence is indicated by the dots and dashed line in FIG. 2a with end 93 of ratchet driver 87 now resting on tooth 95c.

Although the mechanism increases the speed of the production of typed copy, because two characters are printed for each keybutton depression, the operators typing rhythm need not be as fast as is normal without automatic underlining feature. Accordingly, once a character button is pressed, conventional ball interlock 20 of the type described, for example, in US. Pat. 3,086,635 blocks the depression of a second character keylever by the operator until underline interposer 63 has been released by cam follower 129'. This prevents the inadvertent typing of the next character until the end of the two print sequence.

By the operation of this mechanism, the underscore character printing cycle is initiated without escap m n after the printing of the first character in a manner such that the striking of any of the character selection keybuttons will result in the automatic underscoring of the selected character Without an additional operation on the part of the operator, so long as keybutton 65 is retained in the locked-down position. Release of keybutton 65 causes spring 79 to move bar portion 67 upward. Pin 81 on bar portion 67 also moves ratchet driver 87-upwardly to a position where step 91 will no longer be in the path of bladed portion 53 during the rotation of filter shaft 51. The keyboard Will now operate in a normal manner.

It should be understood that although in the described embodiment the underline character is automatically printed, the apparatus can be adapted to automatically print any selected character.

What is claimed is:

1. In a single printing element typewriter having a plurality of character selection buttons, a plurality of character selecting interposers associated therewith, and means for activating said printing element to print a character when its associated button is pressed, said means including a filter shaft and an escapement mechanism; a mechanism for automatically printing an additional selected character comprising:

a control adapted to be positioned so as to place said mechanism in either an operative or an inoperative mode,

a rotatable shaft, said shaft carrying a ratchet Wheel and a cam,

a ratchet driver, said driver having one end adapted to contact and rotate said ratchet wheel, and thereby said shaft and said cam incrementally when said driver is actuated, and having its other end adapted to be contacted by said filter shaft and actuated by the cycling of said filter shaft when said control is position to place said mechanism in an operative mode,

a first cam follower associated with said cam, said cam follower being adapted to disconnect the escapement mechanism of said typewriter on alternate movements, of said cam, and

a second cam follower associated with said cam, said cam follower being adapted to engage and actuate the character selecting interposer associated with said selected character on said alternate movements of said cam,

positioning said control to place said mechanism in an operative mode, activation of a character selection button and the resulting cycling of the filter shaft and printing of the character by the printing element driving said ratchet driver and its associated ratchet Wheel, shaft, and cam causing the first cam follower to disconnect the escapement to print said selected character in the same space as the first printed character, said second cycling of said filter shaft caused by the activation of the selected character interposer again driving the ratchet driver and its associated ratchet wheel, shaft, and cam, to reconnect the escapement mechanism and release said selected character interposer such that the typewriter escapes and is in condition for the typing of the next character.

2. The apparatus of claim 1 wherein said selected character is the underline character.

3. The apparatus of claim 1 wherein said ratchet wheel has a series of teeth and said cam has a series of lobes, said ratchet wheel having twice as many teeth as said cam has lobes such that on alternate cycles of said filter shaft, when said control is positioned to place said mechanism in on operative mode, said cam followers stop on said lobes and disconnect said escapement mechanism and activate said additional selected character interposer.

4. In a single printing element typewriter having a plurality of character selection buttons, a plurality of character selecting interposers associated therewith, and means for activating said printing element to print a character when its associated button is pressed, said means including a filter shaft and an escapement mechanism; a mechanism for automatically printing an additional selected characted comprising:

control means adapted to be positioned so as to place said mechanism in either an operative or an inoperative mode,

cam means,

means for incrementally driving said cam means, said incremental drive means being mounted to be actuated by the cycling of said filter shaft when said control means is positioned to place said mechanism in an operative mode,

a first cam follower associated with said cam means, said cam follower being adapted to disconnect the escapement mechanism of said typewriter on alternate movements of said cam means, and

a second cam follower associated with said cam means,

said cam follower being adapted to engage and actuate the character selecting interposer associated with said additional selected character on said alternate movements of said cam means.

References Cited UNITED STATES PATENTS EDGAR S. BUR'R, Primary Examiner US. Cl. XJR. 197-16 

